1. (a) “Exemption” means an exception from compliance to allow a public water system extra time to comply with a new national primary drinking water regulation, as described in 42 U.S.C. 300g-5.

2. (b) “Unreasonable risk to health” means a situation where:

   1. (1) The MCL for E. coli, nitrate, or nitrite would be exceeded;
   2. (2) The MCL for any other contaminant would be exceeded by a factor of 5 or more; or
   3. (3) If no MCL has been established, the health risk posed by the expected conditions would exceed a reasonable risk as determined using epidemiological studies.

Source. #10617, eff 6-1-14